In order to have a meeting involving participants not located in the same area, a number of technological systems are available. These systems may include video conferencing, web conferencing and audio conferencing.
The most realistic substitute for real meetings is high-end video conferencing systems. Conventional video conferencing systems comprise a number of end-points communicating real-time video, audio and/or data streams over WAN, LAN and/or circuit switched networks. The end-points include one or more monitors, cameras, microphones and/or data capture devices and a codec, which encodes and decodes outgoing and incoming streams, respectively. In addition, a centralized source, known as a Multipoint Control Unit (MCU), is needed to link the multiple end-points together. The MCU performs this linking by receiving the multimedia signals (audio, video and/or data) from end-point terminals over point-to-point connections, processing the received signals, and retransmitting the processed signals to selected end-point terminals in the conference.
The different conferencing systems are, however, not isolated from each other.
Different conferencing technologies now seem to merge, as conference meetings are getting more common and conference technology evolves. It is not unusual to find complete web or audio participants in a traditional video conference.
However, audio and web participants will not achieve the full benefit of the conferencing capabilities when joining a traditional video conference, because of both end-point and system limitations. Audio participants are not able to see the other participants, or data presentations, in the conference, while the video participants are not necessarily even aware of the presence of the audio participants. The latter is sometimes solved by showing an audio participant icon instead of a picture in the video image to indicate that an audio participant is present. This, however, provides little or no information about the participant.